rague-Dawley rats are uninephrectomized and are then immunized with a sheep tibody directed against brush border antigen. This results in a membranous omerulonephritis. This study is designed to study how glomerular sclerosis ogresses. Immunofluorescence studies allow us to study the topography and mposition of extracellular matrix. Preliminary studies show that immune posits disappear within 36 weeks, whereas glomerular sclerosis progresses.